Conventionally, in an air-conditioning management system including a plurality of air-conditioning apparatuses and a centralized monitoring apparatus (embedded device), the centralized monitoring apparatus (embedded device) manages schedule contents of the respective air-conditioning apparatuses. Further, the centralized monitoring apparatus performs schedule control of the air-conditioning apparatuses by transmitting commands to the respective air-conditioning apparatuses in accordance with the schedule contents held therein (see Patent Literature 1, for example).